In many clinical situations it is useful to make multiple medical images of a subject over an extended period of time. For example periodically imaging a cancerous tumor and measuring its size or volume can be a measure of evaluating the effectiveness of a particular therapy. A difficult is that small variations in where the medical image is made can have a huge difference in how the tumor appears in the resulting medical image. It is very critical that in such a sequence of medical images that the scan geometry of subsequent images is as close to the original as possible.
International patent application publication WO 2014/006550 A2 discloses a method of automatic scan planning for subsequent images. The method of this application is particularly useful where the anatomical region being imaged has a rigid structure. The ISMRN-2012 abstract p2567 mentions a rigid registration method for automated scan planning in follow-up examinations. The acquisition geometry of the follow-up scans is computed by applying a rigid registration between the baseline scan and a 3D survey scan at the beginning of the follow-up exam.